The present invention relates to a fuel for vehicles composed of a mixture of alcohol and gasoline.
The conventional fuel for the internal combustion engine has been mainly gasoline, but various countries are now considering use of alcohol fuel to replace oil, whose reserves are dwindling, and to mitigate air pollution and improve combustion efficiency. The use of alcohol alone, however, has the drawback that the engine is hard to start up because alcohol, such as methyl alcohol or ethyl alcohol, has a low vapor pressure and a high heat of vaporization. The prior art relating to fuel composed of gasoline/alcohol mixtures includes MTZ 37 No. 5, 181 (1976), which discloses a mixture of 15 volume % methanol and 85 volume % gasoline as a fuel and SAE Paper 750123, which discloses fuels composed of mixtures of 5 volume % methanol and 95 volume % gasoline, of 10 volume % methanol and 90 volume % gasoline and of 40 volume % methanol and 60 volume % gasoline; these are, however, low in alcohol content and are not mainly composed of alcohol. These fuels, moreover, are defective in that addition of the slightest volume of water causes separation of the gasoline from the alcohol, leading to trouble with the engine operation.
The primary object of the present invention is to provide a fuel for internal combustion engines which is a mixture mainly composed of alcohol, being intended as a countermeasure anticipating the future shortage of oil supplies.
Another object of the present invention is to provide a fuel composed of a mixture of alcohol and gasoline for internal combustion engines which is characterized by good engine startability as well as no separation into two layers through addition of a little water.
Still another object of the present invention is to provide a fuel for internal combustion engines which, because its combustion produces lower emissions of NO.sub.x, CO and HC (hydrocarbons) and less generation of soot than gasoline, is advantageous from the anti-emission and anti-fume standpoints.
Still another object of the present invention is to provide a fuel which is less liable to decompose and deteriorate rubber parts.
Still another object of the present invention is to provide a low-temperature burning fuel which is less liable to deteriorate the lubricant and, accordingly, is capable of reducing seizure due to a broken film of lubricant.
Still another object of the present invention is to provide a fuel which can more easily burn completely than gasoline, accordingly hardly generates carbon and is less liable to cause sticking of a piston-ring.
Still another object of the present invention is to provide a fuel which has a higher octane number and a higher burning efficiency than gasoline.
Other objects and advantages of the present invention will be apparent from the following detailed description of preferred embodiments of the invention.